Digital video apparatus user interface

ABSTRACT

A method for controlling a system for processing stored information stored on a storage medium, the system including a plurality of playmodes (PMs) representing respectively different processing sequences, includes the following steps. A sequence represented by one of the plurality of PMs is played back during play mode of operation. An opportunity is provided to a user, during the play mode of operation, to select a PM from among the plurality of PMs. Then the sequence represented by the selected PM is played back during the play mode of operation. Apparatus for processing information, in this manner includes playback circuitry for retrieving information from the storage medium during a play mode of operation in one of the plurality of PMs. A user control device receives user input. A control means conditions the playback circuitry to assume a play mode of operation, select one of the plurality of PMs during the play mode of operation in response to the user input, and change to retrieve the selected one of a plurality of PMs during the play mode of operation.

This application claims the benefit under 35 U.S.C. § 365 ofInternational Application PCT/US99/16228, filed Jul. 20, 1999, whichclaims the benefit of U.S. Provisional Application Ser. No. 60/093,424,filed Jul. 20, 1998.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a user interface for a digital videoapparatus, and in particular, a user interface for a digital videoapparatus capable of processing a plurality of data blocks according toa user selected playmode.

2. Description of the Related Art

Video signal processing systems that utilize storage media havingdigitally compressed video and audio information recorded thereon cangive the user a vast number of options for controlling playback of avideo title stored on such a media. One such system that is gainingrapid acceptance comprises a video disc player adapted to processinformation stored in accordance with the digital video disc (DVD)specification. The information on a DVD formatted disc is recorded asdiscrete packets of data, in accordance with the applicable video andaudio data compression standards, wherein designated packets carry dataassociated with various data streams, such as alternative video angles,audio tracks, subpicture streams, etc. A disc player reading a DVDformated disc may be controlled to display certain packets of data andskip over others in this manner, the DVD system can be used to preventunauthorized access to information on a particular disc as well asseamlessly provide multiple variations of a video title, such asmultiple camera angles and story endings, in accordance with usercommands.

EP0847197A discloses a device for seamlessly reproducing a bitstreamcontaining noncontinuous system time information. In particular,EP0847197A discloses an authoring system that encodes a multimediabitstream that can be reproduced according to one scenario selected froma plurality of scenarios. The scenarios can be changed during playback,i.e., in response to user selection of a new scenario a new multimediascenario is dynamically generated according to the most recentlyselected scenario. It is also possible to dynamically select andreproduce any one of the plurality of scenarios while reproducing thetitle content according to a desired scenario.

One useful aspect of the DVD system is that it allows the user toplayback the disc contents using one of a plurality of playmodes. DVDformatted discs are generally authored to include one or more videotitles, wherein each video title corresponds to a designated programunit, such as a movie or a television episode. Each video title may inturn be divided into one or more part-of-title units, also calledchapters, wherein each chapter corresponds to a predetermined portion ofthe video title. Under this format, a disc player may be configured toplayback the chapters of a particular video title in one of a pluralityof playmodes. The available playmodes usually include: 1) standard,wherein the disc player plays the disc in the default sequence, usuallyfrom beginning to end; 2) random, wherein the chapters are played backin random order; and 3) program, wherein the chapters are played back ina sequence programmed by the user.

To change a disc player's playmode setting, a user ordinarily must stopdisc playback, call up the appropriate player set-up menu, make thenecessary selections and restart the disc playback. Even if the user isnot directly required to start and stop disc playback, the disc playerautomatically halts playback of the disc and restarts the disc when theuser selects the playmode. If the user wishes to change the playmodesfrequently, the requirement to stop disc playback and navigate the discplayer set-up menu can quickly become annoying. Therefore, it isdesirable to allow the user to dynamically change the disc player'splaymode setting during disc playback, that is, change the playmode asthe video title continues to play in a portion of the display.

SUMMARY OF THE INVENTION

In accordance with the present invention a user interface, method andapparatus is provided for allowing a user to dynamically change aplaymode of a digital video apparatus, in particular a DVD player.Advantageously, the present invention allows the user to dynamicallychange the player's playmode setting without having to stop playback ofa title and then call up and navigate through the player set-up menu.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanyingdrawings, wherein:

FIG. 1 is a block diagram of a digital video disc player suitable forimplementing the dynamic playmode selection feature of the presentinvention;

FIG. 2 is a block diagram illustrating navigation between the discplayer domain and the DVD domain;

FIG. 3 is a diagram of a data structure in accordance with the DVDspecification;

FIG. 4 is a block diagram of a presentation structure in accordance withthe DVD specification;

FIG. 5 is an on-screen display suitable for use with the dynamicplaymode selection feature of the present invention;

FIG. 6 is a flowchart illustrating the steps for implementing thedisplaying of and dynamically selecting among particular ones of aplurality of PMs on a DVD Player; and

FIG. 7 shows, in flowchart form, another embodiment of the method forimplementing the displaying and dynamically selecting among a pluralityof PMs on a DVD disk on a DVD Player in accordance with principles ofthe invention.

DETAILED DESCRIPTION OF THE INVENTION

Although the exemplary embodiment is described with reference to adigital video apparatus adapted to read compressed video and audio datafrom a disc and to process the data in accordance with the DVDspecification, it is to be understood that the present invention may beused in any digital video apparatus capable of processing digital videoand audio data, wherein the data has been stored or is received indistinct data blocks and the data blocks may be played back according toa particular playback sequence.

FIG. 1 is a block diagram showing the basic elements of an exemplarydigital video disc player suitable for implementing the dynamic playmodeselection feature of the present invention. The construction andoperation of these elements are generally known to one of ordinary skillin the art and will not be discussed in detail here. Disc player 24comprises motor and pickup assembly 26 which, under the control of servoprocessor 29, spins the disc and reads the information stored thereon.Preamp 27 and DVD data processing unit 28 translate the electricalpulses from motor and pickup assembly 26 into digital data that can befurther processed by digital audio/video decoder unit 30. DVD dataprocessing unit 28 typically performs functions such as demodulation,error correction and descrambling of the raw data read from the disc sothat the data is in a suitable format for decoder unit 30.

Decoder unit 30 receives the demodulated, error corrected anddescrambled data, processes the data, and provides the appropriate videoand audio signals to a display unit 18, such as a television set.Decoder unit 30 comprises data stream demultiplexer 32 whichdemultiplexes the data from data processing unit 28 into a plurality ofseparate data streams, including a video stream, an audio stream and asubpicture stream, and provides the data streams to their respectivedata decoders. Video decoder 31 receives the video stream and provides avideo signal to mixer 33. Subpicture decoder 34 receives the subpicturestream and provides data to on-screen display (OSD) control 35 whichprovides OSD video signals to mixer 33. The combined video signal frommixer 33 is provided to NTSC/PAL encoder 42 which provides a videosignal that conforms to the appropriate video signal standard to a videodisplay device 18. Audio decoder 36 receives the audio streams from datastream demultiplexer 32 and provide the appropriate audio signals to anaudio system.

Microcontroller 40 controls the operation of disc player 24.Microcontroller 40 is coupled to user control device 41, which maycomprise IR remote control devices, front panel buttons or the like, andtranslates data from user control device 41 to control the operation ofthe various elements of disc player 24 described above. Typically,microcontroller 40 is also configured to control various access featuresof disc player 24 including, but not limited to, parental lock out,decryption of encrypted discs, dialing remote controllers to gain accessto encrypted DVD data. Microcontroller 40 may be embodied in variousforms, including, but not limited to, a dedicated integrated circuit, ora part of a decoder/controller unit. Microcontroller 40 may be comprisedof one of a plurality of suitable controller units, including, but notlimited to STI 5500, manufactured by SGS Thomson.

FIG. 2 illustrates the navigation scheme between player domain 60 anddisc domain 62. As shown in FIG. 2, player domain 60 includes playermenu 61 for allowing the user to select certain operating conditions forthe player, for example parental control ratings. Also, DVD domain 62includes title menu 64 for providing information about the respectivevideo title. On-screen selection from title menu 64 may transfer theuser to title playback block 63, which includes provisions for root menu65. Root menu 65 may be authored onto a disc to provide informationabout available options on the disc including, but not limited to,subtitles, audio tracks and camera angles.

If the disc does not include a root menu 65 authored thereon, it isdesirable to include a means for generating an information display,developed from the actual video and audio information stored on thedisc, which identifies and displays the available options to the user. Aprovision for such means is indicated by information displays block 66.Although information display block 66 is shown inside DVD domain 62, theinformation display is generated by player 24 based on informationauthored on the disc. Alternatively, disc player 24 may be configured toallow the user to select information display block 66 rather than rootmenu 65 even if root menu 65 exists in DVD domain 62.

FIG. 3 illustrates the structure of the program data and control datastored on a disc in accordance with the DVD specification and suitablefor use with disc player 24. The data structure is hierarchical, whereineach data block is divided up into component data blocks, which arefurther divided into smaller component data blocks. Each video titleset, which corresponds to a designated program unit, for example, amovie or an episode of a television show, is comprised of video objectsets, which comprises a plurality of video objects.

Each video object is comprised of a plurality of cells, which may beconsidered a data unit for presentation having a plurality of data unittypes, such as video, audio, subpicture, etc, and corresponds to aprogram segment. Each cell is in turn comprised of a plurality of videoobject units (VOBUs). Each VOBU is comprised of a navigation pack(NAV_PACK) and a plurality of packs, which are subdivided into aplurality of packets. A VOBU generally corresponds to an MPEG-2 Group ofPictures (GOP) with an associated control data structure, the NAV_PACK.The NAV_PACK of each VOBU contains information such as sector addressesof VOBUs relative to the current one (both forwards and backwards intemporal presentation order), and the amount of elapsed time in cellpresentation which corresponds to the current VOBU.

Data stored in accordance with the DVD specification is also logicallyorganized into a presentation structure in order to provide flexibilityin the manner in which the data can be presented. FIG. 4 illustrates thepresentation structure in accordance with the DVD specification andsuitable for use with disc player 24. This presentation structure isoverlaid onto the data structure of FIG. 3. At the base level, thepresentation sequence is defined by programs (PGs) 96, each of whichcomprise a linked list of pointers to cells. A plurality of PGs 96 maybe combined to form a program chain information (PGCI) 94, a pluralityof which may in turn be combined to form program chain (PGC) 92.

During presentation of a video titles, disc player 24 selects theappropriate PGC for loading into a primary table, based on such criteriaas the user selected title and parental rating preference. Thereafter,disc player 24 reads the data stored on the disc based on the linkedlist of pointers contained in the PGs. As is known, disc playersgenerally utilize various look ahead algorithms in order to read thedata from the disc and store the data on a system buffer prior to actualpresentation in order to provide seamless presentation.

As discussed earlier, the storage medium may contain a plurality ofprogram portions, often called chapters, which may be played back indifferent, user selectable orders called playmodes. Also as discussedearlier, a user is able to dynamically call up a menu and make changesto the playmode (PM) of disk player 24. This way, while watching aprogram on the video display being played from a storage medium throughthe disk player, the user is able to call up a menu and change thesedifferent playmodes (PMs) without going through the inconvenience ofstopping the disk playback and trying to restart the video playback eachtime the user wants to make a change.

The different playmodes (PMs) available are (1) standard; (2) random;and (3) programmable PMs. The standard PM allows chapters on a disk tobe played back in the default sequence which is usually from start toend. The random PM plays back chapters in a random order. Theprogrammable PM plays back chapters in the sequence specified by theuser. In response to user input, disk player 24 determines all possiblePMs and which PMs are actually available for actuation. For example, thedisk player 24 determines if the storage medium contains more than onechapter in the video title set. If it does not, the player cannot changethe PM to random or programmable. Further, the disk player 24 determinesif the plurality of chapters on the disk can be used for play back. Forexample, if all chapters are R-rated and the parental control ratingallows only G-rated chapter playback, then the player cannot change thePM to random or programmable.

After determining what PMs are possible and those that are actuallyavailable, a menu is generated (as illustrated in display 110 of FIG.5). If the user changes the PM, the disk player will ask the user if thechange affects only the current title or all future titles. The userwill then use the control device 41 to make the user election. If theplayer elects to change the PM only for the current video title, diskplayer 24 would revert to the prior PM when the playback of the currenttitle is complete, otherwise, the selected PM remains in effect untilchanged by the user.

The various playmodes may be implemented in disk player 24 as follows.In the standard mode, disk player 24 follows the presentation sequencedefined on the disk. The presentation sequence is defined by tables inthe program chain information contained in the control blocks asdescribed above. In the random mode, disk player 24 generates a privatetable that maps each chapter and assigns a specific value to eachchapter based on the order of play. The borders for each chapter areknown based on the program chain information previously loaded in fromthe disk. Thereafter, a random number generator is used to randomlyselect a chapter for presentation and a checking algorithm may beperformed to ensure that each chapter is presented at least once beforeany one chapter is repeated. In the programmable mode, disk player 24accepts the desired sequence from the user and creates a private tablethat lists the boundary information for each of the chapters in thesequence. Thereafter, disk player 24 presents the chapters in accordancewith the listing in the private table. It can be seen that disk player24 creates the supplemental tables from the chapter boundary informationthat is already loaded from the disk in order to alter the presentationsequence.

It is possible to enable and disable the dynamic selection of aplaymode. Enabling/disabling of the method for implementing thedisplaying and dynamically selecting a PM may occur by selecting thedesired mode on a setup option display created by the system's on-screendisplay processor during a setup mode of operation. The setup mode ofoperation, which enables controlling various features such as videoprocessing characteristics, sound characteristics, closed captioning,etc., in addition to PMs selection enable/disable, may be activated, forexample, by pushing a control button on a remote control device. Desiredfeatures/modes/settings are selected from the displayed setup menu byusing buttons on the remote control, all in a known manner.

FIG. 6 is a flowchart illustrating the steps for implementing thedisplaying of and dynamically selecting among particular ones of aplurality of PMs on a DVD Player. In step 127, disc player 24 waits forthe user to send a PLAY command and upon receiving the PLAY commandsearches the disk or video title set for a plurality of PMs. In step128, the user can press a designated button 81 to give the user theopportunity to change playmodes. In step 130, disk player 24 determinesall possible PMs. In step 132, disk player 24 will determine what PMsare available, i.e., those PMs not blocked with a parent block or thosenot enabled. In step 134, an on-screen display 110 is overlaid, in aknown manner, onto the video display generated by the disk player 24 andallows the user to change the PM while continuing to watch the titleplayback in a background portion of the video display. The on screendisplay 110 distinguishes between those PMs present and available andthose that are present and unavailable. The user is allowed to select anavailable PM in step 136. The menu display tracks the user changes ofthe available PMs. In step 138, disk player 24 switches the PM to thenew PM and plays it. In step 140, after disk player 24 switches andplays the new data stream, the on-screen display 110 is no longeroverlaid onto the video display generated by the disk player 24 and thevideo signal processing system returns to a normal display.

FIG. 7 shows, in flowchart form, another embodiment of the method forimplementing the displaying and dynamically selecting among a pluralityof PMs on a DVD disk on a DVD Player in accordance with principles ofthe invention. Steps in FIG. 7 which are the same as those illustratedin FIG. 6 have the same reference number as in FIG. 6, operate in thesame manner to the corresponding steps in FIG. 6 as described above, andwill not be described again here. The arrangement depicted in FIG. 7provides for selectively enabling the mode of operation in which userselects one of a plurality of different PMs. Specifically, FIG. 7includes step 144 following step 128 which tests to determine if theaccess to PM is enabled. If the access to dynamically change the PM isdisabled (A “NO” result at step 146), then step 144 is followed by step142 which exits the routine without providing the user an opportunity tochange the PM. In this case, changing the PM must occur prior toactivation of the playback mode by navigating the usual setup menus asdescribed above if a user desires. Otherwise, step 130, and followingsteps, are performed allowing a user to select a playmode.

It will be apparent to those skilled in the art that although thepresent invention has been described in terms of an exemplaryembodiment, modifications and changes may be made to the disclosedembodiment without departing from the essence of the invention. Also, itis herein recognized that the present playmode selection feature may beimplemented using any one of a number of conventionally known methods,or combination of methods, for controlling the various elements of discplayer 24 described above, for example by using embedded software in amicrocontroller. Therefore, it is to be understood that the presentinvention is intended to cover all modifications as would fall withinthe true scope and spirit of the present invention.

1. A method for controlling a system for processing a plurality of dataunits stored on a storage medium, the system adapted to process asequence of the data units in accordance with one of a plurality ofpossible playmodes comprising standard, random and programmed playmodes,the method comprising the steps of: (A) playing back the data unitsaccording to one of the plurality of playmodes during a PLAY mode ofoperation, (B) determining which of the possible playmodes are actuallyavailable for actuation during playback of the data units on the storagemedium, and generating an on-screen display menu displaying the actuallyavailable playmodes to thereby provide to a user, during the PLAY modeof operation, an opportunity to select another one of the actuallyavailable playmodes, the plurality of playmodes including a standardplaymode representing a default sequence, a random playmode representinga random sequence and programmed playmode representing a sequencespecified by a user, without interrupting playback of a current sequenceof data units, and (C) in response to user selection of a new playmode,changing the playback sequence of the data units in accordance with thenewly selected playmode.
 2. The method of claim 1, wherein step (B)comprises the step of generating the on-screen display menu includesoverlaying the menu onto a video display which allows the user to selectone of the plurality of playmodes while continuing to watch the playbackof the data units in a background portion of the video display.
 3. Themethod of claim 2, wherein step (B) is preceded by the step ofdetermining whether a mode of operation enabling selection of one of theplurality of playmodes during the PLAY mode of operation is enabled; andperforming steps (B) and (C) only if the mode of operation enablingmodification of the plurality of playmodes during the PLAY mode ofoperation is enabled.
 4. The method of claim 3, wherein the step ofdetermining whether user modification of a playmode is enabled ispreceded by the step of determining whether the system is in the PLAYmode of operation.
 5. The method of claim 4, wherein: the systemcomprises a DVD player and the storage medium comprises a DVD disk; theDVD disk includes a plurality of chapters; and the plurality ofplaymodes represent respectively different sequences of chapters.
 6. Themethod of claim 1, step (C) is preceded by the step of allowing the userto select whether the newly selected playmode will be effective for allfuture playbacks or only the current playback.
 7. Apparatus forprocessing data units stored on a storage medium according to aparticular playback sequence, the apparatus comprising: playbackcircuitry for accessing and processing data units stored on the storagemedium during a PLAY mode of operation; a user control device forreceiving user input; and a control unit, coupled to the playbackcircuitry and the user control device, for conditioning the playbackcircuitry to activate the PLAY mode of operation and process the dataunits in a particular playback sequence in response to user selection ofone of a plurality of playmodes, wherein the control unit determineswhich of a plurality of possible playmodes are actually available foractuation during playback of the data units on the storage medium and iscoupled to an on-screen display control for generating an on-screendisplay menu displaying the actually available playmodes for providingto a user during the PLAY mode of operation an opportunity to selectfrom among the actually available playmodes associated with the dataunits, the plurality of playmodes including a standard playmoderepresenting a default sequence, a random playmode representing a randomsequence and programmed playmode representing a sequence specified by auser, without interrupting the PLAY mode of the playback circuitry, and,in response to user selection of a new playmode, changing the playbacksequence of the data units in accordance with the newly selectedplaymode.
 8. The apparatus of claim 7, wherein the on-screen displaymenu is overlaid over the video for allowing the user to select one ofthe plurality of playmodes while watching a playback of a currentsequence of data units in a background portion of the video display. 9.The apparatus of claim 7, wherein the control unit determines whether amode of operation enabling selection of one of the plurality ofplaymodes during the PLAY mode of operation is enabled; and provides anopportunity to select a new playmode without interrupting the PLAY modeonly if the mode of operation enabling modification of the plurality ofplaymodes during the PLAY mode of operation is enabled.
 10. Theapparatus of claim 7, wherein the playback circuitry comprises means foraccessing and processing data from a DVD disk and the storage mediumcomprises a DVD disk, wherein the DVD disk includes a plurality ofchapters; and the plurality of playmodes represent respectivelydifferent sequences of chapters.
 11. The apparatus of claim 7, whereinthe control unit provides an on-screen display to allow the user toselect whether the newly selected playmode will be effective for allfuture playbacks or only the current playback.